Move common/gtest:gtest_coro to folly/experimental/coro

Reviewed By: yfeldblum

Differential Revision: D23847355

fbshipit-source-id: b5fbf5bea515111d34962100af0f44ae11e0845f

folly/experimental/coro/GtestHelpers.h

@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <gtest/gtest.h>
+
+#include <folly/experimental/coro/BlockingWait.h>
+#include <folly/experimental/coro/Task.h>
+
+/**
+ * This is based on the GTEST_TEST_ macro from gtest-internal.h. It seems that
+ * gtest doesn't yet support coro tests, so this macro adds a way to define a
+ * test case written as a coroutine using folly::coro::Task. It will be called
+ * using folly::coro::blockingWait().
+ *
+ * Note that you cannot use ASSERT macros in coro tests. We'll need to add a
+ * CO_ASSERT macro if it's needed. EXPECT macros work fine.
+ */
+// clang-format off
+#define CO_TEST_(test_case_name, test_name, parent_class, parent_id)\
+class GTEST_TEST_CLASS_NAME_(test_case_name, test_name) : public parent_class {\
+ public:\
+  GTEST_TEST_CLASS_NAME_(test_case_name, test_name)() {}\
+ private:\
+  void TestBody() override;\
+  folly::coro::Task<void> co_TestBody();\
+  static ::testing::TestInfo* const test_info_ GTEST_ATTRIBUTE_UNUSED_;\
+  GTEST_DISALLOW_COPY_AND_ASSIGN_(\
+      GTEST_TEST_CLASS_NAME_(test_case_name, test_name));\
+};\
+\
+::testing::TestInfo* const GTEST_TEST_CLASS_NAME_(test_case_name, test_name)\
+  ::test_info_ = /* NOLINT */ \
+    ::testing::internal::MakeAndRegisterTestInfo(\
+        GTEST_STRINGIFY_TOKEN_(test_case_name), \
+        GTEST_STRINGIFY_TOKEN_(test_name), NULL, NULL, \
+        ::testing::internal::CodeLocation(__FILE__, __LINE__), /* NOLINT */ \
+        (parent_id), \
+        parent_class::SetUpTestCase, \
+        parent_class::TearDownTestCase, \
+        new ::testing::internal::TestFactoryImpl< /* NOLINT */ \
+            GTEST_TEST_CLASS_NAME_(test_case_name, test_name)>);\
+void GTEST_TEST_CLASS_NAME_(test_case_name, test_name)::TestBody() {\
+  folly::coro::blockingWait(co_TestBody());\
+}\
+folly::coro::Task<void> GTEST_TEST_CLASS_NAME_(test_case_name, test_name)::co_TestBody()
+// clang-format on
+
+/**
+ * TEST() for coro tests.
+ */
+#define CO_TEST(test_case_name, test_name) \
+  CO_TEST_(                                \
+      test_case_name,                      \
+      test_name,                           \
+      ::testing::Test,                     \
+      ::testing::internal::GetTestTypeId())
+
+/**
+ * TEST_F() for coro tests.
+ */
+#define CO_TEST_F(test_fixture, test_name) \
+  CO_TEST_(                                \
+      test_fixture,                        \
+      test_name,                           \
+      test_fixture,                        \
+      ::testing::internal::GetTypeId<test_fixture>())